Background: Numerous studies have investigated methods of predicting postoperative pulmonary complications (PPCs) in lung cancer surgery, with chronic obstructive pulmonary disease (COPD) and low forced expiratory volume in 1 second (FEV1 ) being recognized as risk factors. However, predicting complications in COPD patients with preserved FEV 1 poses challenges. This study considered various diffusing capacity of the lung for carbon monoxide (DLCO ) parameters as predictors of pulmonary complication risks in mild COPD patients undergoing lung resection. Methods: From January 2011 to December 2019, 2,798 patients undergoing segmentectomy or lobectomy for non-small cell lung cancer (NSCLC) were evaluated. Focusing on 709 mild COPD patients, excluding no COPD and moderate/severe cases, 3 models incorporating DLCO , predicted postoperative DLCO (ppoDLCO ), and DLCO divided by the alveolar volume (DLCO /VA) were created for logistic regression. The Akaike information criterion and Bayes information criterion were analyzed to assess model fit, with lower values considered more consistent with actual data. Results: Significantly higher proportions of men, current smokers, and patients who underwent an open approach were observed in the PPC group. In multivariable regression, male sex, an open approach, DLCO <80%, ppoDLCO <60%, and DLCO /VA <80% significantly influenced PPC occurrence. The model using DLCO /VA had the best fit. Conclusion Different DLCO parameters can predict PPCs in mild COPD patients after lung resection for NSCLC. The assessment of these factors using a multivariable logistic regression model suggested DLCO /VA as the most valuable predictor.

Purpose: Heart failure (HF) and atrial fibrillation (AF) frequently coexist, with over 50% patients with HF having AF, while onethird of those with AF develop HF. Differences in obesity-mediated association between HF and HF-related AF among Asians and Europeans were evaluated. Materials and Methods: Using the Korean National Health Insurance Service-Health Screening (K-NHIS-HealS) cohort and the UK Biobank, we included 394801 Korean and 476883 UK adults, respectively aged 40–70 years. The incidence and risk of HF were evaluated based on body mass index (BMI). Results: The proportion of obese individuals was significantly higher in the UK Biobank cohort than in the K-NHIS-HealS cohort (24.2% vs. 2.7%, p<0.001). The incidence of HF and HF-related AF was higher among the obese in the UK than in Korea. The risk of HF was higher among the British than in Koreans, with adjusted hazard ratios of 1.82 [95% confidence interval (CI), 1.30–2.55] in KNHIS-HealS and 2.00 (95% CI, 1.69–2.37) in UK Biobank in obese participants (p for interaction <0.001). A 5-unit increase in BMI was associated with a 44% greater risk of HF-related AF in the UK Biobank cohort (p<0.001) but not in the K-NHIS-HealS cohort (p=0.277). Conclusion Obesity was associated with an increased risk of HF and HF-related AF in both Korean and UK populations. The higher incidence in the UK population was likely due to the higher proportion of obese individuals.

Objective: The cutaneous manifestation of decompression sickness (DCS) known as cutis marmorata (CM) is generally mild, but it is often accompanied by severe DCS or may be a prognostic sign. We aimed to analyze the clinical course of patients with CM to improve our understanding of CM. Methods: From January 2016 to December 2020, a retrospective cohort single-center study was conducted on patients with acute DCS who underwent emergency recompression therapy. We analyzed their data and the clinical outcomes after recompression therapy. In addition, we reviewed relevant literature. Results: A total of 341 people were enrolled during the study period. Of them 94 (27.6%) patients presented with CM and the symptoms appeared at an average of about 60.5 minutes after surfacing. Among the CM patients, 76.6% had accompanying DCS type II, and in 23.4%, had accompanying DCS type I (P=0.011). With single recompression therapy, 88.3% of patients with CM immediately recovered. Among these 95.4% of patients with DCS type I and 86.1% with DCS type II recovered immediately. However, there were no statistical differences in the immediate treatment outcomes according to the delay time from the onset of symptoms to recompression therapy, accompanying symptomatic DCS classification, and recompression modalities. Ultimately, all the patients recovered from CM. Conclusion CM by itself can be considered a mild DCS in terms of treatment progress, but prompt treatment is required to prevent complications. In addition, greater focus is needed on other accompanying DCS symptoms in patients with CM, and the treatment method should be determined accordingly.

Background and Objectives: Atrial fibrillation (AF) is associated with decreased cardiac resynchronization therapy (CRT) benefits compared to sinus rhythm (SR). Effective biventricular (BiV) pacing is a determinant of CRT success, but AF can interfere with adequate BiV pacing and affect clinical outcomes. We investigated the effect of device-detected AF on clinical outcomes and optimal BiV pacing in patients with heart failure (HF) treated with CRT. Methods: We retrospectively analyzed 174 patients who underwent CRT implantation between 2012 and 2019 at a tertiary center. The optimal BiV pacing percentage was defined as ≥98%. Device-detected AF was defined as an atrial high-rate episode ≥180 beats per minute lasting more than 6 minutes during the follow-up period. We stratified the patients without preexisting AF at pre-implantation into device-detected AF and no-AF groups. Results: A total of 120 patients did not show preexisting AF at pre-implantation, and 54 had AF. Among these 120 patients, 19 (15.8%) showed device-detected AF during a median follow-up of 25.1 months. The proportion of optimal BiV pacing was significantly lower in the device-detected AF group than in the no-AF group (42.1% vs. 75.2%, p=0.009). The devicedetected AF group had a higher incidence of HF hospitalization, cardiovascular death, and all-cause death than the no-AF group. The device-detected AF and previous AF groups showed no significant differences regarding the percentage of BiV pacing and clinical outcomes. Conclusions For HF patients implanted with CRT, device-detected AF was associated with lower optimal BiV pacing and worse clinical outcomes than no-AF.

Background: Traditional right ventricular apical pacing can cause electrical–mechanical dyssynchrony. Therefore, physiological conduction system pacing was considered and became the reason for developing His bundle pacing (HBP). Recently, left bundle branch area pacing (LBBAP) has been implemented, which overcomes the shortcomings of HBP. Most initial large LBBAP studies reported that LBBAP was achieved through a lumenless pacing lead (LLL) with a fixed helix design; however, it is unavailable in Korea. LBBAP delivery sheaths using a conventional standard styletdriven pacing lead (SDL) with an extendable helix design are currently available in Korea. In this review, we describe the methods and procedural skills required to perform the LBBAP using conventional SDL.Main body LBBAP has emerged as a new physiological CSP modality and has shown a stable and lower capture threshold and achieved a similarly paced QRS duration compared to HBP. It has also demonstrated stable early outcomes for feasibility and safety with a high success rate. Furthermore, the application of LBBAP has recently been extended to a resynchronization strategy. The LBBAP with SDL requires different handling and lead preparation owing to differences in lead and helix designs. Reported procedure-related acute complications of LBBAP include septal per‑ foration during the procedure, pneumothorax, pocket infection, pocket hematoma, and lead dislodgements occur‑ ring during follow-up. Conclusion LBBAP with conventional SDL has similar implant success rates, procedural safety, and pacing character‑ istics as LBBAP with LLL. However, LBBAP with SDL requires different handling and lead preparation from that of LLL owing to the differences in the lead and helix designs.

Background and Objectives: We investigated whether extra-pulmonary vein (PV) ablation targeting a high maximal slope of the action potential duration restitution curve (Smax) improves the rhythm outcome of persistent atrial fibrillation (PeAF) ablation. Methods: In this open-label, multi-center, randomized, and controlled trial, 178 PeAF patients were randomized with 1:1 ratio to computational modeling-guided virtual Smax ablation (V-Smax) or empirical ablation (E-ABL) groups. Smax maps were generated by computational modeling based on atrial substrate maps acquired during clinical procedures in sinus rhythm. Smax maps were generated during the clinical PV isolation (PVI). The V-Smax group underwent an additional extra-PV ablation after PVI targeting the virtual high Smax sites. Results: After a mean follow-up period of 12.3±5.2 months, the clinical recurrence rates (25.6% vs. 23.9% in the V-Smax and the E-ABL group, p=0.880) or recurrence appearing as atrial tachycardia (11.1% vs. 5.7%, p=0.169) did not differ between the 2 groups. The postablation cardioversion rate was higher in the V-Smax group than E-ABL group (14.4% vs. 5.7%, p=0.027). Among antiarrhythmic drug-free patients (n=129), the AF freedom rate was 78.7% in the V-Smax group and 80.9% in the E-ABL group (p=0.776). The total procedure time was longer in the V-Smax group (p=0.008), but no significant difference was found in the major complication rates (p=0.497) between the groups. Conclusions Unlike a dominant frequency ablation, the computational modeling-guided V-Smax ablation did not improve the rhythm outcome of the PeAF ablation and had a longer procedure time.

Background: Cardiac resynchronization therapy (CRT) is an effective treatment option for patients with heart failure (HF) and left ventricular (LV) dyssynchrony. However, the problem of some patients not responding to CRT remains unresolved. This study aimed to propose a novel in silico method for CRT simulation. Methods: Three-dimensional heart geometry was constructed from computed tomography images. The finite ele‑ ment method was used to elucidate the electric wave propagation in the heart. The electric excitation and mechani‑ cal contraction were coupled with vascular hemodynamics by the lumped parameter model. The model parameters for three-dimensional (3D) heart and vascular mechanics were estimated by matching computed variables with measured physiological parameters. CRT effects were simulated in a patient with HF and left bundle branch block (LBBB). LV end-diastolic (LVEDV) and end-systolic volumes (LVESV), LV ejection fraction (LVEF), and CRT responsiveness measured from the in silico simulation model were compared with those from clinical observation. A CRT responder was defined as absolute increase in LVEF ≥ 5% or relative increase in LVEF ≥ 15%. Results: A 68-year-old female with nonischemic HF and LBBB was retrospectively included. The in silico CRT simu‑ lation modeling revealed that changes in LVEDV, LVESV, and LVEF by CRT were from 174 to 173 mL, 116 to 104 mL, and 33 to 40%, respectively. Absolute and relative ΔLVEF were 7% and 18%, respectively, signifying a CRT responder.In clinical observation, echocardiography showed that changes in LVEDV, LVESV, and LVEF by CRT were from 162 to 119 mL, 114 to 69 mL, and 29 to 42%, respectively. Absolute and relative ΔLVESV were 13% and 31%, respectively, also signifying a CRT responder. CRT responsiveness from the in silico CRT simulation model was concordant with that in the clinical observation. Conclusion This in silico CRT simulation method is a feasible technique to screen for CRT non-responders in patients with HF and LBBB.

Background: Conventional modality requires several days observation by Holter monitor to differentiate atrial fibril‑ lation (AF) between Paroxysmal atrial fibrillation (PAF) and Non-paroxysmal atrial fibrillation (Non-PAF). Rapid and practical differentiating approach is needed. Objective: To develop a machine learning model that observes 10-s of standard 12-lead electrocardiograph (ECG) for real-time classification of AF between PAF versus Non-PAF. Methods: In this multicenter, retrospective cohort study, the model training and cross-validation was performed on a dataset consisting of 741 patients enrolled from Severance Hospital, South Korea. For cross-institutional validation, the trained model was applied to an independent data set of 600 patients enrolled from Ewha University Hospital, South Korea. Lasso regression was applied to develop the model. Results: In the primary analysis, the Area Under the Receiver Operating Characteristic Curve (AUC) on the test set for the model that predicted AF subtype only using ECG was 0.72 (95% CI 0.65–0.80). In the secondary analysis, AUC only using baseline characteristics was 0.53 (95% CI 0.45–0.61), while the model that employed both baseline characteris‑ tics and ECG parameters was 0.72 (95% CI 0.65–0.80). Moreover, the model that incorporated baseline characteristics, ECG, and Echocardiographic parameters achieved an AUC of 0.76 (95% CI 0.678–0.855) on the test set. Conclusions Our machine learning model using ECG has potential for automatic differentiation of AF between PAF versus Non-PAF achieving high accuracy. The inclusion of  Echocardiographic parameters further increases model per‑ formance. Further studies are needed to clarify the next steps towards clinical translation of the proposed algorithm.

Excessive salt intake induces hypertension, but several gamma-aminobutyric acid (GABA) supplements have been shown to reduce blood pressure. GABAsalt, a fermented salt by L. brevis BJ20 containing GABA was prepared through the post-fermentation with refined salt and the fermented GABA extract. We evaluated the effect of GABA-salt on hypertension in a high salt, high cholesterol diet induced mouse model. We analyzed type 1 macrophage (M1) polarization, the expression of M1 related cytokines, GABA receptor expression, endothelial cell (EC) dysfunction, vascular smooth muscle cell (VSMC) proliferation, and medial thicknesses in mice model. GABA-salt attenuated diet-induced blood pressure increases, M1 polarization, and TNF-α and inducible nitric oxide synthase (NOS) levels in mouse aortas, and in salt treated macrophages in vitro. Furthermore, GABA-salt induced higher GABAB receptor and endothelial NOS (eNOS) and eNOS phosphorylation levels than those observed in salt treated ECs. In addition, GABA-salt attenuated EC dysfunction by decreasing the levels of adhesion molecules (E-selectin, Intercellular Adhesion Molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1]) and of von Willebrand Factor and reduced EC death. GABA-salt also reduced diet-induced reductions in the levels of eNOS, phosphorylated eNOS, VSMC proliferation and medial thickening in mouse aortic tissues, and attenuated Endothelin-1 levels in salt treated VSMCs. In summary, GABA-salt reduced high salt, high cholesterol diet induced hypertension in our mouse model by reducing M1 polarization, EC dysfunction, and VSMC proliferation.

Purpose: Cardiovascular health (CVH) status is associated with several cardiovascular outcomes; however, correlations between changes in CVH status and risk of sudden cardiac death (SCD) are unknown. We aimed to evaluate associations between changes in CVH status and risk of SCD and all-cause death in older adults. Materials and Methods: We used data from the Korea National Health Insurance Service-Senior cohort database (2005–2012). Six metrics from the American Heart Association (smoking, body mass index, physical activity, blood pressure, total cholesterol, and fasting blood glucose) were used to calculate CVH scores. Changes in CVH status between two health checkups were categorized as low to low, low to high, high to low, and high to high. Results: We included 105200 patients whose CVH status for an initial and follow-up health checkup (2-year interval) was available. During a median of 5.2 years of follow-up after a second health checkup, 688 SCDs occurred. Compared to patients with a persistent low CVH status, those with a consistently high CVH status had a reduced risk of SCD [adjusted hazard ratio (HR), 0.69; 95% confidence interval (CI), 0.56–0.86] and all-cause death (adjusted HR, 0.74; 95% CI, 0.69–0.78). The risk of all-cause death followed similar trends. However, an inconsistent linear relationship was observed for changes in CVH status and the risk of SCD, but not of all-cause death. Conclusion Maintaining a high CVH status was associated with future risks of SCD and all-cause death among an older adult population.